As originally planned, the experiment was supposed to last for two weeks. But the results were so troubling that it was ended after six days.

It occurred in 1971, and involved Stanford University psychology professor Philip Zimbardo and a team of graduate students who recruited middle class college students and divided them into squads of guards and prisoners to examine how the power dynamics of authority and imprisonment impacted on people.

Stanford Prison Experiment¬†is a psychological thriller inspired by the famous experiment with Billy Crudup in the role of Dr. Zimbardo. The film screens at the RPL Theatre on Thursday Jan. 21 and Saturday Jan. 23 at 9:30 p.m., Friday Jan. 22 at 7 p.m. and Sunday Jan. 24 at 2:30 p.m. Here’s the trailer: